Finding the Fourth Proportional to 16,815.78, 23,205.42 and 9,261.72

Step by Step Solution

1. Step 1: Write the proportion equation
   16,815.78 : 23,205.42 = 9,261.72 : x
2. Step 2: Convert to fraction form
   16,815.78/23,205.42 = 9,261.72/x
3. Step 3: Cross multiply
   16,815.78x = 23,205.42 × 9,261.72
4. Step 4: Simplify right side
   16,815.78x = 214,922,102.52
5. Step 5: Solve for x
   x = 214,922,102.52/16,815.78
6. Step 6: Final answer
   x = 12,780.98